Rhodamin dye.



HERMANN BOEDEKER, OF HUOHST-ON-THE-MAIN, GERMANY, ASSIGNOR TO THEFARB\VERKE, VORMALS MEISTER, LUOIUS dz BR'UNING, OF SAME RHODAEVIIN DYE.

SPECIFICATION forming part of Letters Patent No. 641,184, dated January9, 1900 Application filed December 29, 1897. Serial No. 664,437.($pecimens.)

To all whom it may concern.-

3e it known that I, HERMANN BOEDEKER, doctor of philosophy,a subject ofthe Emperor of Germany, residing at Hochst-on-the-Main,

. Germany, have invented certain new and usefullmprovements in theManufacture of Dyestuffs from Phthalio Acid Rhodamins and AromaticBases, (for which I have obtained Letters Patent in Germany, No. 75,500,dated July 1, 1-893; in England, No. 14,207, dated July 22, 1893, and inFrance,No. 231,700,dated July 22,1893,) of which the following is aspecification.

This invention relates to the production of dyestufis from phthalic acidrhodamins and aromatic bases.

I have found that by the action of aromatic bases upon the alkylatedmeta-amidophenolphthaleins (rhodamins) under appropriate conditions awhole series of new derivatives may be produced, which distinguishthemselves from the dyestuffs used as primary material by their bluertints, and particularly by their great affinity to the vegetable fiber.

I illustrate the manufacture by the following example: Ten kiloshydrochlorid of diethylrhodamin are given to twenty mono methylanilin,to which are slowly added, with good cooling and stirring, 2.4kilosphosphorus oxych1orid,in order that the temperature does not rise aboveto centigrade. After some hours standing the mass is poured into Water,the excess of methylanilin is dissolved on addition of hydrochloricacid, and the dyestuff is precipitated with common salt. To

purify, it is again dissolved with warm water and filtered. From thissolution, to which, if too diluted, some salt is added, the new productcrystallizes out in small green laminae of metallic luster, formingafter filtration and drying adark-red powder of green luster soluble inwater with a red color. Its alcoholic solution shows avividfluorescence. It is soluble in concentrated sulfuric acid with a yellowcolor and dyes mordanted cotton a fiery pink. Tetraethylrhodamin reactsexactly as diethylrhodamin.

Instead of the monomethylanilin mentioned in the above example otheraromatic secondary and tertiary bases, as monoethylamin, dilnethylanddiethyl-anilin, chinolin, monethyl-ortho-toluidin, dibenzylanilin may becombined with rhodamins to dyestuffs in the manner described,whichdistinguish themselves from the primary material by their stronger basiccharacter, their bluer tints, greater fastness to the vegetable fiber,and greater solubility in water. Primary aromatic bases, however, arenot applicable for the process described.

Having now described my invention, what I claim is 4 As a new dyestuff,the product resulting from the simultaneous action of phosphoroxychloridand one of the specified aromatic bases upon symmetric diethylrhodaminas herein described, being a red powder of green metallic luster,soluble in water with a red color, in alcohol with a vivid fluorescence,and in concentrated sulfuric acid with ayellow color, crystallizing fromwater in green laminae of metallic luster, and dyeing cotton a fierypink, substantially as set forth.

In testimony that I claim the foregoing as

